Safer non-flammable lithium-ion batteries are coming

Thanks to a material that makes the bottom of ships non-sticky

Anyone with a basic understanding of statistics can see that lithium-ion batteries are pretty safe (certainly safer than gasoline). There are billions and billions of them in daily use around the world, in everything from phones to tablets to laptops to electric cars. But they sometimes do malfunction and catch fire, especially after severe accidents. It doesn't make them unsafe, but it means there's still room for improvement, which is exactly what researchers at University of North Carolina at Chapel Hill are working on.

While studying a material that prevents marine life from sticking to the bottom of ships (!), they might have found a replacement for the only inherently flammable component of lithium-ion batteries, the electrolyte.

"When we discovered that we could dissolve lithium salt in this polymer, that's when we decided to roll with it," said Dominica Wong, a graduate student in DeSimone's lab who spearheaded the project. "Most polymers don't mix with salts, but this one did—and it was nonflammable. It was an unexpected result."

This new class of non-flammable electrolytes is based on functionalized perfluoropolyethers (PFPEs). The researchers report that these electrolytes exhibit thermal stability beyond 200 °C /392 °F.

The next step is to optimize electrolyte conductivity and improving battery cycling characteristics for this new chemistry. If that is successful, commercialization should be possible, which would be a great thing for electric cars.